Growth Rate of the Hibiscus Syriacus 'Lucy'

Reddish-pink “Lucy” grows well massed in groups in the garden.

Also known as shrub althea, the rose of Sharon cultivar “Lucy” (Hibiscus syriacus “Lucy”) is a deciduous shrub bearing bright reddish-pink flowers over a long period, usually from early summer into mid-fall. Its slow growth rate means it does not reach full height quickly. But if you are patient, its low-maintenance nature and abundant blooms recommend it as a landscape plant.

Identification

“Lucy” is winter hardy to U.S. Department of Agriculture plant hardiness zones 5 through 8. Its 3-inch flowers are red to pink, with five petals and a showy stamen. Flowers stay open for a single day and then close at night and are done. They form on new growth, so you can prune at any time of year. This, however, is usually unnecessary as the plant grows quite slowly and grows in a tight upright formation.

Growth Rate

This vigorous, upright, multi-stemmed shrub has a relatively slow growth rate, usually only gaining a foot or less in the course of a growing season. Its typical height is 6 to 8 feet, while it can spread to widths of 4 to 6 feet. Other rose of Sharon varieties can grow as tall as 12 feet and spread to 10, though “Lucy” usually will not. Under ideal conditions the growth rate may increase to moderate rather than slow. Because its spread is narrower than its height, it usually assumes a vase-shaped formation.

Culture

Rose of Sharon cultivars like “Lucy” will grow in full sun or partial shade, but prefer lots of sun. For the plant to look its best, however, you should plant in a location where it will be protected from hot afternoon sun. “Lucy” likes moisture, and though it is drought-tolerant, will not flower well without lots of it. Low-water environments also encourage leaf drop, so if you want abundant blooms, keep soil consistently. Although the plant tolerates poor soils, it prefers rich ones.

Garden Uses

The rose of Sharon “Lucy” is best beloved for its abundant flowers throughout the height of summer and into early fall, when not much else is blooming. It works well as a specimen plant or massed in groups, and can be used as a foundation planting, hedge or screen. It can also be used as a shrub border. Although it will not perform optimally, “Lucy” does tolerate drought, as well as wet soil and salty air, making it suitable for a range of landscapes.